Self-righting lamp structures commonly are used in highway work zones, construction sites, campsites, and other uses in which it is desirable to have a selectively positionable light source at various locations that are subject to change. Such light fixtures typically comprise an elongated support member having a lamp assembly at its upper end and an enlarged, weighted, generally spherical or rounded self-righting counterweight member or segment at its lower end. Such light fixtures are desirable because they are easy to install in their upright position simply as an incident to placing the light fixture at the desired location. Moreover, if the light fixture is accidentally hit or moved, such as can occur in work zones, the fixture will automatically right itself to the up right position. While ostensibly simple in appearance, construction, and function, such self-righting lamp structures present a number of unexpected problems in their design, manufacture, and usage.
At the outset, the spherical self-righting segment can add considerable weight to the light fixture, making it difficult or awkward to pick-up, handle, or move the light fixture as is frequently necessary during usage. Moreover, excessive counter weighting of the self-righting spherical segment can cause the light fixture to be moved to an upright position with such force it can cause injury to personnel or damage to the light fixture if striking a nearby object. Furthermore, the rounded or spherical bottom of the self-lighting segment can cause the light-fixture to rock excessively and for long periods each time the fixture is repositioned or moved from the upright position. On the other hand, forming a flat bottom on the spherical self-righting segment can cause what is referred to as “slapping”, with the flat bottom slamming against a flat floor surface with excessive force each time it is rocked during self-righting positioning. Such self-righting counterweight segments also can make it difficult to orient the light fixture in a particular “non-upright” position for particular lighting applications. While in some instances it may be desirable to position the fixture on its side for downward direction of lighting, the rounded counterweight segment, being designed to upright the light fixture, generally will not permit such side positioning. Likewise, it can be cumbersome to mount or selectively position a reflector about the light assembly of the fixture as is often desired for particular light direction.
Since the elongated support member that extends from the self-righting counterweight segment commonly is a relatively small diameter cylindrical structure, it also can be difficult to mount electrical components, cooling fans, and the like within the support structure of the light fixture as is commonly required. Furthermore, air holes required in the side of the light fixture housing for permitting the circulation of cooling air to the lamp during operation can allow the undesirable entry of rain water, or other contaminates in the surrounding environment, which can hinder proper operation of the electrically operated lamp.